Preparation of therapeutic substances



Patented July 19, 1949 UNITED STATES PATENT OFFICE PREPARATION OFTHERAPEUTIC SUBSTANCES No Drawing. Application October 3, 1945, SerialNo. 620,174. In Great Britain October 17, 1944 4 Claims.

This invention relates to the preparation of substances havingtherapeutic properties.

In the co-pend-ing patent application Serial No. 562,920, filed November10, 1944, a method is set forth for the preparation of stable compoundsof amino-acridines with sulphathiazole which have certain advantages incomparison with 2:8- diaminoacridine sulphate (proflavine) itself,especially in cases in which solutions approaching neutrality areessential. The process therein described consists in effecting a directreaction between molecular proportions of sulphathiazole and theamino-acridine or between equivalent amounts of salts which, onadmixture, give rise to those reactants.

It has now been discovered that stable compounds, having definiteantistreptococcal properties, of amino-acridines withsulphanilylaminopyrimidines, such as for example,sulphadimethylpyrimidine, (2-4 -aminobenzenesulphonylamino- 4:6dimethylpyrimidine) may be produced by similar processes.

Thus, according to the present invention, such compounds are formed byeffecting reactions between molecular proportions of an aminoacridineand a sulphanilylaminodimethylpyrimidine or between equivalent amountsof salts which give rise to those reactants on admixture.

In order that the invention may be fully understood and readily carriedinto effect, some examples of processes in accordance therewith will nowbe described.

Example 1 In the preparation of a compound of sulphadimethylpyrimidineand S-aminoacridine, sulphadimethylpyrimidine (5.56 gms.:0.02 mol.) isdissolved in boiling alcohol (200 ml.). 5-aminoacridine (3.88 gms.:0.02mol.) is also added. The whole gives a clear solution which is filteredand cooled. Pale yellow crystals separate which melt at 229 C. withdecomposition.

Example 2 In the preparation of a compound of sulphadimethylpyrimidineand 2:8 diaminoacrid-ine, a solution of sulphadimethylpyrimidine (2.78gms.:0.01 mol.) and 2:8-diaminoacridine (2.09 gms.:0.01 mol.) in boilingwater (250 ml.) is filtered and cooled. The product is filtered off,washed with water and dried at 100 C.

The product separates in orange coloured prisms, which melt at 136-137C., and retains a molecule of water after drying at 100 C.

We claim:

1. Process for the manufacture of a new compound which consists inreacting 2-su1phanilamido-4.6-dimethyl pyrimidine with a member of thegroup consisting of 5-a1ninoacridine and 2.8-diaminoacridine.

2. Process as claimed in claim 1 in which the reactants are produced insitu by admixture and addition of their salts.

3. A new compound consisting of 2-sulphanilamido-4.6-dimethyl pyrimidinecombined with 5- aminoacridine in equal molecular proportions, saidcompound being yellow and crystalline and melting with decomposition at229 0., having antiseptic properties and being stable in aqueoussolution, but decomposable into its constituents by treatment with acidor alkali.

4. A new compound consisting of 2-sulphanilamido-4.6-dimethyl pyrimidinecombined with 2:8-diaminoacridine in equal molecular proportions, saidcompound being an orange crystalline solid retaining one molecule ofwater and melting at 136 to 137 C., having antiseptic properties andbeing stable in aqueous solution, but decomposable into its constituentsby treatment with acid or alkali.

HERBERT AUBREY STEVENSON. WALLACE FRANK SHORT.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,145,799 Powell Jan. 31, 19392,145,800 Stuart Jan. 31, 1939 2,351,333 Gysin June 13, 1944 2,370,561Mecca Feb. 27, 1945 FOREIGN PATENTS Number Country Date 114,894Australia Mar. 17, 1942 OTHER REFERENCES Journ. Indian Chem. Soc., vol.16, pp. 364-368 (1939); bid., vol. 18, pp. 25-28 (1941).

Ganapathi: Proc. Indian Acad. 801., vol. 12-A, pp. 274283 (Sept. 1940).

Northey: Chem. Rev., vol. 27, page 119 (Aug. 1940).

